CD24 notes

Deep research (just deep-research-falcon human CD24 --fallback perplexity-lite) failed in this
environment (no provider available); research done directly from cached publications and UniProt.

Identity and localization

• 80-aa precursor: signal peptide 1-26, mature peptide 27-59, C-terminal propeptide 60-80 removed;
  GPI anchor on amidated Gly59 (UniProt P25063, by similarity). Two N-glycosylation sites; extensively O-glycosylated.
• UniProt: "SUBCELLULAR LOCATION: Cell membrane; Lipid-anchor, GPI-anchor."
• PMID:16390867
• Conclusion: outer leaflet of plasma membrane, entire mature protein extracellular; raft-enriched.
  No cytoplasmic domain PMID:11313396.

Ligand functions

• Siglec-10: PMID:31367043; anti-phagocytic
  "don't eat me" signal on tumours. PMID:19264983;
  CD24-Siglec-G/10 represses DAMP (HMGB1, HSP70, HSP90) responses (mostly mouse data).
• P-selectin: PMID:9129046; platelet adhesion to DU145 PMID:15633604.

Signaling

• Associates with FGR (SW2) and LYN (K562) PMID:8753773; raft LYN activation and apoptosis after cross-linking in Burkitt lymphoma PMID:11313396.
• Calcium flux / oxidative burst after antibody cross-linking [PMID:2153173, PMID:8223854].
• Reduces CXCR4 signaling/raft association PMID:16390867.

Curation issues

• PMID:8753773 protein binding row WITH UniProtKB:P11362 (FGFR1) — paper studies c-fgr (FGR, P09769); recorded as source defect.
• Wnt signaling NAS (PMID:16532032): CD24 is a Wnt target-gene readout, removed.
• Added NEW: signaling receptor binding (Siglec-10 ligand) and negative regulation of immune response (PMID:31367043).